High-voltage circuit breakers are generally known. The at least one device for diverting the outward expanding insulating gas flow from the region between the two arcing contacts is designed to conduct the insulating gases, which are heated by an electric arc, to other regions of the high-voltage circuit breaker. In this way, the hot insulating gas not only can relax, but is also cooled down because it mixes with cold insulating gas that is present in the flow-through regions and because of a heat transfer to the components of the high-voltage circuit breaker through which it flows.
For a state of the high-voltage circuit breaker in which the two main contacts and the two arcing contacts are no longer connected, it is thus critical that the insulation capacity achieved with the insulating gas between the two main contacts is always high enough, so that an electrical separation is constantly ensured. This is tantamount to saying that the insulating capacity of the insulating gas between the two separated main contacts, meaning the so-called electrical resistance of the two main contacts, must always be ensured.
The requirement to use as little of the insulating gas as possible has resulted in smaller and smaller regions of the high-voltage circuit breaker that are filled with insulating gas while, at the same time, the density of the insulating gas is also selected to be lower and lower. It is thus possible that the two insulating gas flows, which are conducted outside of the insulating nozzle from both directions approximately along the longitudinal axis in the direction toward the main contacts, no longer have sufficient insulating capacity, so that the electrical separation of the two main contacts is no longer ensured in the above-explained state of the high-voltage circuit breaker. In particular, at least one of the two insulating gas flows entering the region of the two main contacts can contain insulating gas that is at least hot enough, so that the electrical separation of the two main contacts is no longer securely guaranteed. Among other things, this follows from the fact that hot insulating gas has a lower insulating capacity than cold insulating gas.